16421040040 has 64 divisors (see below), whose sum is σ = 38310829200. Its totient is φ = 6327078912.

The previous prime is 16421040029. The next prime is 16421040043. The reversal of 16421040040 is 4004012461.

It can be written as a sum of positive squares in 8 ways, for example, as 563682564 + 15857357476 = 23742^2 + 125926^2 .

It is a junction number, because it is equal to n+sod(n) for n = 16421039993 and 16421040020.

It is not an unprimeable number, because it can be changed into a prime (16421040043) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 485934 + ... + 518626.

Almost surely, 2^16421040040 is an apocalyptic number.

16421040040 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16421040040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19155414600).

16421040040 is an abundant number, since it is smaller than the sum of its proper divisors (21889789160).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16421040040 is a wasteful number, since it uses less digits than its factorization.

16421040040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33166 (or 33162 counting only the distinct ones).

The product of its (nonzero) digits is 768, while the sum is 22.

The spelling of 16421040040 in words is "sixteen billion, four hundred twenty-one million, forty thousand, forty".